Flexible storage receptacles for use with pre-existing wallets are described in U.S. Pat. No. 4,105,057 (hereinafter referred to as the "'057 patent") and also in U.S. Pat. No. 4,942,913 (hereinafter referred to as the "'913 patent"). These devices are destined for "after market" applications where a retailer who sells conventional wallets also offers special inserts for the wallets. The flexible receptacle shown in the '057 patent is designed for use with a wallet or billfold and provides extra storage space for carrying additional credit cards. The flexible receptacle may; also be used to provide a credit card holder for billfolds which are not so equipped. Although it would be possible to place photographs within these receptacles, in order to view the photo, the photo would have to be removed from the receptacle. Repeated insertions and removals will eventually damage the photo.
The '913 patent shows a "sub-wallet" for use with a main wallet. The sub-wallet carries important items which the wallet owner always needs, while the remainder of the wallet carries items which are not absolutely necessary. In a pinch, the owner can subsist on the sub-wallet alone, and does not require the contents of the main wallet. Although photos could be placed in the wallet or the sub-wallet, it would not be possible to view more than one of these photos unless one were to remove them from the wallet or sub-wallet, thereby causing the photos to become worn and mutilated over time.
Other types of wallets are described in U.S. Pat. Nos. 5,431,207 and 5,775,398. These feature intricate compartmental arrangements for accommodating devices such as calculators, along with holders for accommodating various sundries. Such wallets are very complex, with the unfortunate result that the owner has no choice but to carry around the elaborate features of the wallet, some of which are never used.
U.S. Pat. No 5,595,401 describes a book for holding credit cards. Similar to the receptacle of the '057 patent (above), the card book provides additional carrying capacity for a wallet, or, alternatively, may be used as a dedicated credit card holder for wallets which have no card holders. The credit card book is not intended for repeated insertion into, and removed from, the wallet. Rather, in use, the credit card is removed from the book, and the book remains in the wallet.